Fig. 1

HOTAIR is detected in serum of GBM patients. a HOTAIR levels are higher in serum from brain tumor patients relative to controls. Serum from normal patients (n = 40) or patients suffering from either pilocytic astrocytoma (n = 6), diffuse astrocytoma (n = 6), GBM (n = 43), oligodendroglioma (n = 4), anaplastic oligodendroglioma (n = 7), were analyzed for the levels of HOTAIR. HOTAIR levels were detected by qRT-PCR and normalized to the corresponding GAPDH levels and relative to an internal control serum. b HOTAIR expression in GBM serum is significantly higher than in normal control patients. The expression level of serum HOTAIR in 43 GBM and 40 control patients were detected and analyzed using Mann-Whitney test (P < 0.001). c Serum HOTAIR can be a significant diagnostic indicator for GBM patients. Serum HOTAIR can discriminate GBM and normal patients with an area under the ROC curve value of 0.913 (P < 0.0001). Note that sensitivity and specificity of the assay was 86.1% and 87.5%, respectively. d Serum HOTAIR levels correlate with GBM tumors. The HOTAIR levels in 15 paired tumors and serum from GBM patients were measured by qRT-PCR. Pearson correlation analysis demonstrated a medium correlation of serum HOTAIR levels and the corresponding tumor HOTAIR levels (r = 0.7342, P < 0.01)